平板膜生物反应器用于工业区污水处理厂尾水深度处理中试研究

介绍了采用平板膜对工业区污水处理厂二级处理尾水进行深度处理中试试验,试验结果表明在通量0.5～0.6 m3/（m2·d ）情况下系统能稳定运行,出水水质有较大提升。系统最适运行条件为曝气强度1150L/（m2·h）、污泥浓度12g/L、抽吸时间9 min、抽停时间1 min、最大抽吸压力-10 kPa。膜污染试验发现次氯酸钠和柠檬酸联合清洗方式对跨膜压差（TMP）恢复效果最佳,TMP能恢复到初始的98％以上。     

膜系统生产运行指标及参数研究

为保证膜过滤系统的正常运行,需要经常检查膜的各项运行指标参数。对清泰水厂膜系统的运行通量、TMP、特定通量以及修正后的特定通量等运行指标进行了比较,根据其优缺点,选择特定通量为膜运行的主要参考指标,范围在12~16LMH/m[L/(h·m2)m],根据不同的情况选择不同的参考值,避免了过多运行指标的盲目性,减轻了值班人员的工作量。同时也很容易发现系统运行是否发生了异常,提高了效率,延长了膜的使用寿命,保证膜滤后水的安全。     

膜组器结构优化及工艺运行参数调整研究

膜生物反应器技术是当前最先进的污水处理技术之一,在世界范围内广泛应用于市政污水处理领域。该技术有着出水水质好、占地小、污泥排放量少、运行稳定、操作简单等优点。但是一次性投资及运行费用较高等问题阻碍了其在污水处理中的推广应用。传统连续曝气控制膜污染是膜生物反应器最大耗能部分,约占整个系统能耗的60%左右。为有效降低膜生物反应器工艺的运行费用,同时保证曝气控制膜污染的效果,笔者从膜片间距,结合曝气方式、气水比3方面进行研究,以优化膜组器结构实现膜生物反应器工艺运行费用的根本性降低。经研究发现当膜片间距为24 mm,气水比为30:1,曝气方式为曝气10 s停10 s的频率时,曝气控制膜污染的效果与连续曝气控制膜污染效果相似,甚至更好。以此研究为基础,确定了针对北京市郊区县农村排放污水的膜生物反应器工艺的运行参数:污泥浓度为(5～12)g/L;气水比为(20～40)∶1;每(2～3)个月进行1次在线清洗,清洗药剂浓度为3 g/L;自吸泵抽停比为7∶1。     

浸没式超滤膜处理地表水的膜污染影响因素试验研究

采用中试考察浸没式膜处理地表水的膜污染影响因素,主要通过运行压力的变化,确定膜通量、混合液性质、膜材料对膜污染状况的影响.试验结果表明:膜通量高于临界膜通量越多,膜运行压力增长速度越快,试验用膜的临界膜通量为20 L/(m2·h);混合液的浊度及有机物含量越高,膜运行压力增长越快,膜污染越严重;温度升高可以减轻膜污染;对于相同的膜通量,PVDF超滤膜运行压力要低于PVC合金超滤膜,PVDF膜的抗污染能力要强于PVC合金膜.     

膜生物反应器处理生活污水运行效能研究

采用一体式中空纤维膜膜生物反应器(MBR)处理生活污水，稳定运行 结果表明：进水COD质量浓度180～350mg/L，COD容积负荷可达到2.2～2.8kg/( m³•d)，出水COD质量浓度13.2～22.8mg/L，COD的平均去除率为95.9％。膜组件对整个反应体系的净化效果起着重要的强化作用。     

新疆阿克苏污水处理厂的设计及运行

新疆阿克苏污水处理厂首次采用水解-交替式内循环活性污泥工艺(AICS工艺)处理城市污水。水解池停留时间为2.6 h,好氧AICS工艺停留时间为5.3 h,运行周期为6 h,污泥负荷采用0.34 kgBOD/(kgMLSS·d)。实际运行结果表明,出水COD,BOD和SS均达到国家一级排放标准。其工程投资成本仅为669元/m3,处理费用为0.34元/m3。     

射流间歇曝气氧化沟的生化特性研究

将低压射流曝气系统应用于氧化沟中,采用2h曝气,2h停曝的连续运行方式,系统CODCr去除率高达92%,BOD5去除率高于94%,NH3—N去除率达87%,TN去除率高于50%,TP去除率高于72%;测定SVI<80mL/g,活性污泥的外源比耗氧速率为63.7mgO2/(gMLVSS·h)。污泥内源呼吸比耗氧速率为9.8mgO2/(gMLVSS·h)。与常规的活性污泥法相比较,污泥碳化比耗氧速率可提高2～3倍,污泥内源呼吸比耗氧速率提高1～2倍,污泥活性得到较大提高。     

污泥杂质分离器的工艺设计与运行参数优化研究

污泥杂质分离器是一种借助微网机械筛分原理、可实现污泥中细颗粒物(小于1 mm)去除的污泥预处理技术。为优化污泥杂质分离器的工艺设计与运行参数,针对初沉污泥,模拟了不同密度的杂质,研究其工艺筛分机理;比选了不同孔径的筛网,分析其筛分效率;同时,引入微网临界通量的概念,研究了不同微网间距和杂质浓度对微网临界通量的影响,确定最佳工艺参数。结果表明:重质杂质优先被分离,其次是悬浮杂质,轻质杂质易形成浮渣,头发丝易缠绕微网组件和曝气管;20~80目的微网具有较好的杂质分离效果;微网间距2.5 cm和杂质浓度15 g/L的条件下微网临界通量可达到4.7 m3/(m2·h)。     

纯膜MBBR在城市溢流污染治理中的应用研究

城市溢流污染是造成城市水体黑臭的主要原因之一。为减少溢流污水对城市河道的污染,长江大保护项目中某污水处理厂采用装备化纯膜MBBR系统对溢流污水进行处理。系统采用雨季及旱季两种运行模式,出水COD、氨氮、TP、SS的平均浓度分别为25.3mg/L、1.35mg/L、0.15mg/L、5.86mg/L。旱季及雨季运行时系统对氨氮的去除负荷分别为0.61gN/(m2·d)、0.5gN/(m2·d)。大幅削减了污染物通过溢流作用进入自然水体,在源头端控制了水体黑臭的发生。     

UASB-BAF工艺处理油脂废水

将UASB(升流式厌氧污泥床)与BAF(曝气生物滤池)工艺联合用于实际工程处理油脂废水,在有效预处理条件下,CODCr、SS和油脂的去除率可分别达到97%、86%和75%,出水可达<污水综合排放标准>(GB 8798-1996)一级排放要求.工程总投资费用为351.20万元,水处理运行费用为1.41元/m3.     

一体式膜生物反应器膜污染防治理论研究

从理论上分析了一体式膜生物反应器内曝气量与污水流量、反应器设计高度、主副腔过流面积的关系,膜外污染错流临界流速与抽吸压力及主腔宽度的关系,膜管内污染的临界速度与膜管径、膜壁吸力的关系,并得出采用化学方法消除膜污染的原理。     

延缓膜生物反应器膜污染的技术措施探讨

膜生物反应器(MBR)是膜分离技术和污水生物处理技术有机结合产生的一种新型污水处理工艺,与传统污水处理工艺相比具有很多优点,但膜污染是限制膜生物反应器广泛应用的关键因素.介绍了膜污染的定义,系统论述了膜污染的研究进展,着重从改良膜的性质,改善污泥混合液的特性和优化膜分离操作条件3个方面介绍了国内外有效延缓膜污染的技术措施.     

Function of dynamic membrane in self-forming dynamic membrane coupled bioreactor.

The Self-Forming Dynamic Membrane Coupled Bioreactor (SFDMBR), which uses coarse pore-sized material to separate solid and liquid in bioreactors, has some advantages compared with MBR using micro-/ultra-filtration membranes, for example, low module cost and high flux. The cake layer and gel layer formed on the surface and in the pores of the material during filtration played an important role, called self-forming dynamic membrane (DM), which mainly consisted of activated sludge. In this study, the function of DM in pollutant removal was investigated. It was found that DM could remove some organic matter (12.6 mg L(-1) on average) and total nitrogen (3.01 mg L(-1) on average) in the supernatant. Colloids and organic nitrogen were partly removed by DM while DOC, ammonia nitrogen and nitrate nitrogen removal by DM varied from negative to positive, which resulted from the combination of various biological activities, e.g. nitrification, biological utilization and so on. DO concentration in DM decreased with the depth and reached zero at about 1.5-2.5 mm depth. The organic degradation activity and nitrification activity of the biomass suspended in the bioreactor were higher than those of the biomass in the cake layer, which might be caused by the low DO concentration and low organic pollutant content in DM.     

Application of PTFE membrane for ammonia removal in a membrane contactor

The feasibility of a membrane contactor system for ammonia removal was studied. The mass transfer coefficient was used to quantitatively compare the effect of various operation conditions on ammonia removal efficiency. Effective removal of ammonia was possible with a Polytetrafluoroethylene (PTFE) membrane contactor system at all tested conditions. Among the various operation parameters, contact time and solution pH showed significant effect on the ammonia removal mechanism. The overall ammonia removal rate was not affected by influent suspended solution concentration unlike other pressure driven membrane filtration processes. Also the osmotic distillation phenomena which deteriorate the mass transfer efficiency can be minimized by preheating of influent wastewater. A membrane contactor system can be a possible alternative to treat high strength nitrogen wastewater by optimizing operation conditions such as stripping solution flow rate, influent wastewater temperature, and influent pH.     

Quantitative analysis of biological effect on membrane fouling in submerged membrane bioreactor.

The objective of this study is to investigate solids concentration and extracellular polymeric substance (EPS) effects on the membrane fouling in the submerged membrane bioreactor. The relationship between the solids retention time (SRT) and the amount of EPS is observed in three lab-scale MBRs. Additionally, the EPS effect on membrane fouling is quantified by calculating the specific cake resistance (alpha) using an unstirred batch cell test. By observing the sludge over a long period under various SRT scenarios, a wide range of EPS and membrane fouling data is obtained. These observations provide sufficient evidence of the functional relationship between SRT, EPS and alpha. As SRT decreases, the amount of EPS bound in sludge floc becomes higher in the high MLSS condition (> 5,000 mg/L). The amount of EPS in the sludge floc has positive influence on alpha. A sigmoid trend between EPS and alpha is observed and the functional relationship obtained by dimensional analysis is consistent with the experimental results.     

膜生物反应器的污泥特性和膜污染研究

对中试规模的缺氧—好氧—膜生物反应器(A/O—MBR)处理城市污水进行研究,并对好氧池内活性污泥的特性和膜污染后期的影响因素进行了分析。试验结果表明:污泥浓度(MLSS)对CODCr、氨氮等各指标的处理效果均有影响。与传统活性污泥工艺相比,膜生物反应器污泥负荷小、表观产泥率低。     

Characteristics of membrane fouling in submerged membrane bioreactor under sub-critical flux operation.

Recently, the membrane bioreactor (MBR) process has become one of the novel technologies to enhance the performance of biological treatment of wastewater. Membrane bioreactor process uses the membrane unit to replace a sediment tank, and this can greatly enhance treatment performance. However, membrane fouling in MBR restricts its widespread application because it leads to permeate flux decline, making more frequent membrane cleaning and replacement necessary, which then increases operating and maintenance costs. This study investigated the sludge characteristics in membrane fouling under sub-critical flux operation and also assessed the effect of shear stress on membrane fouling. Membrane fouling was slow under sub-critical flux operation. However, as filamentous microbes became dominant in the reactor, membrane fouling increased dramatically due to the increased viscosity and polysaccharides. A close link was found between membrane fouling and the amount of polysaccharides in soluble EPS. The predominant resistance was the cake resistance which could be minimized by increasing the shear stress. However, the resistance of colloids and solutes was not apparently reduced by increasing shear stress. Therefore, smaller particles such as macromolecules (e.g. polysaccharides) may play an important role in membrane fouling under sub-critical flux operation.     

垃圾渗滤液膜浓缩液超声强化直接接触膜蒸馏处理工艺EI北大核心CSCD

为提高膜蒸馏在处理垃圾渗滤液膜浓缩液时渗透通量的稳定性,设计了一种新型的超声强化直接接触膜蒸馏(US-DCMD)装置,试验研究了超声对膜渗透通量的影响,并采用电子显微镜、X射线能量色散光谱等手段分析超声对膜面污染层的影响。试验结果表明:在60W的超声辐照条件下,渗透通量最高提升19.4%,并在膜溶液浓缩系数达到4时,相对渗透通量最高维持在77.1%,而未施加超声的相对渗透通量在膜溶液浓缩系数为2时降至20.7%;膜面的主要污染物为CaCO_(3)及腐殖酸,其中CaCO_(3)是限制膜渗透通量的主要因素;超声使污染层钙的质量分数从25.6%降至15.0%,并且不会引起有机物的降解或改性;超声辐照使膜面污染层不均匀且存在裂隙,减少了污染层厚度,维持了渗透通量的稳定。     

Effect of membrane characteristics on the performance of membrane bioreactors for oily wastewater treatment

Influence of membrane material and pore size on the performance of a submerged membrane bioreactor (sMBR) for oily wastewater treatment was investigated. The sMBR had a working volume of about 19 L with flat sheet modules at the same hydrodynamic conditions. Five types of micro- and ultra-polymeric membranes containing cellulose acetate (CA), cellulose nitrate (CN), polyamide (PA), polyvinylidene difluoride (PVDF) and polyethersulfone (PES) were used and their filtration performance in terms of permeability, permeate quality and fouling intensity were evaluated. Characterization of the membranes was done by performing some analysis such as pore size distribution; contact angle and scanning electronic microscopy (SEM) microphotograph on all membranes. The quality of permeates from each membrane was identified by measuring chemical oxygen demand (COD). The results showed more irreversible fouling intensity for membranes with larger pore size which can be due to more permeation of bioparticles and colloids inside the pores. Membrane characteristics have a major role in the preliminary time of the filtration before cake layer formation so that the PA with the highest hydrophilicity had the lowest permeability decline by fouling in this period. Also, the PVDF and PES membranes had better performance according to better permeate quality in the preliminary time of the filtration related to smaller pore size and also their better fouling resistance and chemical stability properties. However, all membranes resulted in the same permeability and permeate quality after cake layer formation. An overall efficiency of about 95% in COD removal was obtained for oily wastewater treatment by the membranes used in this study.     

Effect of a suspended carrier on membrane fouling in a submerged membrane bioreactor.

In an attempt at membrane fouling control, a kind of cylindrical plastic suspended carrier was added in a submerged membrane bioreactor (SMBR) and its effect was investigated in this study. According to the transmembrane pressure (TMP) profiles and the sludge characteristics in comparative runs with and without suspended carriers, it was found that the suspended carriers added in SMBR had two effects on membrane fouling: one was the positive effect of mechanically scouring the membrane surface and the other was the negative effect of breaking up sludge flocs. Sludge particle size distribution change was mainly responsible. It was suggested to apply the suspended carrier at higher MLSS concentration and lower carrier dose based on the consideration for retarding sludge breakage caused by the carrier. The experiment was conducted under higher MLSS (8 gL(-1)) and lower carrier dose (carrier volume/total volume = 10/). The TMP increase was effectively retarded by added suspended carriers compared to the system without addition of the carriers. The effect of suspended carriers on membrane fouling at high MLSS concentration was verified.